Question

我正在创建一个有6个赛季的sqlite数据库的android书，但listview需要几秒钟才能加载数据。我知道我实施onscroll方法来实现这一点，但我不知道如何管理它我的代码是：

public class list_story extends ListActivity{
private database db;
private String[] Name;

private String sea;
Context c;
@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    requestWindowFeature(Window.FEATURE_NO_TITLE);
    setContentView(R.layout.list_story);
    db = new database(this);
    Bundle ex = getIntent().getExtras();
    sea = ex.getString("sea");
    refresh();
    setListAdapter(new AA());


}

class AA extends ArrayAdapter<String>{
    public  AA(){   
    super(list_story.this,R.layout.row_list,Name);
}
    @Override
    public View getView(final int position, View convertView, ViewGroup parent) {

        LayoutInflater in = getLayoutInflater();
        View row = in.inflate(R.layout.row_list, parent,false);
        txt.setText(Name[position]);
        return (row);

    }   

}
 private void refresh(){
     db.open();
     int s =db.Story_count("content", sea);
     Name = new String[s];
     Fav=new String[s];
     Tasvir=new String[s];
     Scientific=new String[s];
     English=new String[s];

     for (int i = 0; i < s; i++) {
         Name[i]=db.Story_display(i, sea, "content", 1);
         Fav[i]=db.Story_display(i, sea, "content", 4);
         Tasvir[i]=db.Story_display(i, sea, "content", 5);
         Scientific[i]=db.Story_display(i, sea, "content", 6);
         English[i]=db.Story_display(i, sea, "content", 7);

    }
     db.close();

} }

Answer 1

基本上每当您尝试给新视图充气时，您都会真正夸大新视图。问题在于，如果您有100多个项目可以放入列表视图，那么您已经定义了100多个视图。这非常低效。使用ViewView的ViewHolder模式，或使用RecyclerView。更好的是使用RecyclerView。网上有很多关于这两者的信息。只需查看＆＃34;如何在列表视图中使用ViewHolder＆＃34;

Answer 2

如果您只使用单个文本字段和db，我会建议您使用simpleCursorAdapter：

A sub-pattern begins with a ?, *, +, @, or ! character followed by a pattern-list 
enclosed in parentheses. Pattern-lists themselves can contain sub-patterns. 
The following list describes valid sub-patterns.

?(pattern-list) 
        Matches exactly zero or exactly one occurrence of the specified pattern-list.

*(pattern-list) 
        Matches zero or more occurrences of the specified pattern-list.

+(pattern-list) 
        Matches one or more occurrences of the specified pattern-list.

@(pattern-list) 
        Matches exactly one occurrence of the specified pattern-list.

!(pattern-list) 
        Matches any string that does not match the specified pattern-list.

如果您还有其他问题，请查看这个很棒的示例https://thinkandroid.wordpress.com/2010/01/09/simplecursoradapters-and-listviews/

listview上的sqlite数据库

2 个答案: